This invention relates to an inscribed transmission device including a crescent-shaped space between an external gear and an internal gear circumscribingly in mesh with each other.
Such an inscribed transmission device has been known as disclosed in Japanese Patent Application Publication No. 58-47,592 filed by the applicant or assignee of this case.
FIG. 1 illustrates one embodiment of the Japanese Patent Application Publication. As shown in FIG. 1, the device comprises a driving gear a, a driven gear b, a floating ring gear c circumscribingly engaging the driven gear b, and a toothed or cog belt d extending about the driving gear a and the floating ring gear c.
With the device shown in FIG. 1, the floating ring gear c is maintained in mesh with the driven gear b with the aid of a tension of the toothed belt d. Under certain conditions, however, unintensional disengagement of the driven and floating gears b and c would occur to cause so-called "skipping of teeth" which makes it impossible to transmit the torque from the driving gear a to the driven gear b.